The average claim paid by the federal flood insurance program broke records in 2017 by surpassing $100,000 for the first time, raising new questions about the program’s financial viability, according to an E&E News analysis of federal data.

The records also show that property owners in two states—Louisiana and Texas—have collected more than half of the $69 billion in claims paid by the National Flood Insurance Program since 1973. Homeowners in two counties—Orleans Parish in Louisiana and Harris County in Texas—have collected nearly a quarter of the claims. Orleans Parish sustained the brunt of Hurricane Katrina in 2005, and Harris County was devastated by Hurricane Harvey in 2017.

E&E News analyzed 2.4 million payments by the flood insurance program. The records were released last week by the Federal Emergency Management Agency, which runs the NFIP, along with information about 50 million insurance policies. The agency plans to disclose more data, which experts hope will help guide decisions about development in flood-prone areas.

The findings come as Congress tries to revise the struggling insurance program.

“This is a really big step,” said Anna Weber, a senior policy analyst at the Natural Resources Defense Council, which released its own analysis that shows flood claims “are piling up across the nation, even in areas far from the shore.”

The newly released data embellishes previously known trends related to the climbing cost of payments from the public flood insurance program. The average annual cost of claims grew from $257 million in the 1980s to $659 million in the 1990s and to $2.8 billion in the 2000s, E&E News found. Those figures involve payments from only the NFIP, the nation’s top flood insurer.

By accounting for the growing number of NFIP policies over the past 40 years, E&E News found that the average annual payment—which indicates the extent of flood damage and the value of property—soared to a record $110,815 in 2017.

The previous record was $83,198, set in 2005 after Hurricanes Katrina and Rita. The average NFIP payment in 1978 was $5,072.

The record payments in 2017 were driven largely by the billions of dollars in property damage from Hurricane Harvey’s winds and record rainfall. The record capped a 40-year period of growing claims, whose average size has exceeded inflation and the value of homes.

“The most likely explanation is that you have more people in coastal flood zones, where you get storm surge,” said R.J. Lehmann, director of insurance at the libertarian R Street Institute. Storm surge exacerbates damage through violent waves and rising sea levels.

The cost of repairs from flooding also has increased as knowledge about the health dangers of mold grows, Lehmann said.

Weber of the NRDC said the increase in average payments resulted from “more damaging events and more valuable property in flood areas.”

Some of the increase in the average payment since 1978 likely results from Congress raising the maximum claim from $200,000 to $350,000 in 1994. The maximum payment has not changed since then. The number of policies has also grown; the program now covers about 5.1 million policies.

The average claim will continue to increase, putting additional pressure on taxpayers to bail out the insurance program, said Dena Adler, a climate law fellow at the Columbia Law School’s Sabin Center for Climate Change Law. “Climate change threatens to make it a whole lot worse,” Adler said. “Sea-level rise will continue to exacerbate other flooding-related problems.”

E&E News also found a high degree of geographic concentration in payments from the NFIP.

Property owners in Louisiana and Texas collected $35.6 billion, or 51% of the $69.4 billion paid out since 1973.

Property owners in five states—Louisiana, Texas, New Jersey, New York and Florida—collected $52.5 billion in payments, which is 76% of the total.

Property owners in 12 counties that were hit by Hurricanes Katrina or Harvey and Superstorm Sandy collected half of all the insurance payments. Those 12 counties are Harris, Galveston and Jefferson in Texas; Orleans, Jefferson, St. Bernard, St. Tammany and East Baton Rouge parishes in Louisiana; Nassau and Suffolk counties on Long Island, N.Y.; Ocean County, N.J.; and Harrison County, Miss.

Many properties in those 12 counties have suffered repeated flood damage over the years and filed multiple flood claims. The cost of insuring some properties often exceeds their value.

“We’ve got to figure out a way to use NFIP as a driving mechanism to bring down risk and repeat flooding in these areas that keep flooding over and over again,” said Laura Lightbody, project director of the flood-prepared communities initiative at the Pew Charitable Trusts. “We’re not going to stop it from flooding.... But we and communities can figure out ways to reduce that risk and the impacts.”

A bill approved last week by the House Financial Services Committee would help communities mitigate flood risks, particularly in areas that have been flooded repeatedly. Visualizing the damage through NFIP claims data “can help Congress drive mitigation dollars toward those areas that need it the most,” Lightbody said.

The NFIP payments following Katrina, Sandy and Harvey drove the program deeply into debt with federal taxpayers. The program is supposed to be self-supporting, but it loses money when claims exceed premiums.

Congress canceled a $16 billion debt in October 2017, in effect forcing taxpayers to pay for insurance claims. The NFIP now has a debt of $20.5 billion, which some members of Congress have suggested canceling.

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